Electric incadescent lamp.



O. SCHALLER.

ELECTRIC INGANDESCENT LAMP. APPLICATION IILED JULY 24, 1911.

Patented Jan. 30, 1912.

m H V v MQ 0 Z Z %W M WJ. 3W V 0. SGHALLER.

ELECTRIC INCANDESGENT LAMP.

APPLIGATION FILED JULY 22', 1911.

1,016,099. Patented Jan. 30, 1912.

2 SHEETS-SHEET 2.

d gig/2y;

5 O insulating devices.

UNITED STATES PATENT OFFICE.

OTTO SCHALLER, F StlDENDE, NEAR BERLIN, GERMANY.

ELECTRIC INCANDESCENT LAMP.

To all whom it may concern:

Be it known that I, OTTO SCHALLER, a

citizen of the German Empire, and residing at Siidendc, near Berlin, German Empire,

have invented certain new and useful Improvements in Electric Incandescent Lamps, of which the following is a full. clear, and exact description.

Hitherto the current feed from the outside to the filament in electric incandescence lamps has been efi'ected by means of thin wires, fused in the glass walls ofthe bulbs. Platinum wires were generally employed for this purpose or wires of other metal, the

.coetiicient of expansion of which was approximately the same as that of the glass, in order, as far as possible, to avoid leakage atthe points of fusion and consequent cracking of the glass on the alternate heating and cooling of the bulbs and the feed wires.

Apart from fusing in the feed wires, attempts have been made to effect a reliable sealing of the feed wires by means of packing, such as impregnated paper or rubber or varnish coating, but in connection with all these substances, the unavoidable variations of temperature inevitably resulted in leakage, due mainly to the fact that the surfaces to be sealed, even in the case of conical to entirely prevent differences of tension between the feed wires and the material surrounding the same on expansion and contraction due to differences of temperature-- especially if the Wires are somewhat thick,

which diti'ercnces of tension result in leakage due to cracks produced and the consequent entrance of air into the bulb.

According to the present invention the sealing of the conductors to be introduced 5 into the lamp is attained, in contradistinction to those methods hitherto known, by means of surfaces situated laterally of the feed wires, which contact with corresponding sealing surfaces of the glass bulb or of These sealing surfaces, which may be of any desired size compatible with the size of the lamps, render it possible to keep the current feed wires themselves Specification of Letters Patent.

Application filed July 24, 1911.

Patented Jan. 30,1912.

Serial No. 640,215.

in tight connection with the lamp, 2'. e. the bulb, solely by means of the atmospheric air pressure, which, in its turn again, enables the contacting sealing surfaces to move one on the other, on varying expansion or contraction of the materials of which they consist. The expansion or contraction of the current feeds and the contacting materials will show but very slight displacement in the registering scaling surfaces. Grease or a liquid packing material may be inserted between the sealing surfaces, which are advantageously ground on each other, in order to insure an air tight contact of the surfaces. In connection with these sealing surfaces extending laterally of the current feed conductors, any known sealing medium may be employed, such for instance as rubber or aper, which may be impregnated, or any (nown liquid or labyrinth packing. All

these sealing devices need only possess the slightest elasticity, since the difference of expansion of the lamp materials in question is of the slightest. The laterally extending sealing surfaces. which may be arranged on terminals, wires, rods, enable also the employment of current conductors of any de sired diameter, so that high pressure current lamps may be employed, without any restriction as regards the strength of current.

In the accompanying drawing some cmbodiments of the invention are illustrated.

Figure 1 is a vertical section showing a simple form of the invention, Fig. 2 is a similar section of a lamp for alternating current, Fig. 3 is apart section drawn to a larger scale of a liquid seal, Fig. 4 is a vertical section showing the conductor in the. form of a plate and Fig. 5 shows the arrangement of contacting surfaces not applied directly to the bulb.

In Fig. l the body of the lamp consists substantially of a spherical glass or quartz bulb (1 having two necks I) and c. the upper edges of which are advantageously ground. On to these surfaces are fitted the current feed conductors (1 and c by means of their plate-like advantageously ground enlargements f and g. To the parts of the feed couductors, which extend into the bulb 11. the incandescence body It is screwed or welded. which body may consist of several wires. rods, bows or plates. This attachment may be elfected by tiist introducing the incandescence body through one of the openings 1) or 0 into the lamp and then pushing both ends through their respective openings far enough out of the lamp, to etfect the connection with the current feed conductors outside the lamp. These lamps may be worked with continuous or alternating current.

In Fig. 2 a lamp is illustrated, which is adapted for alternating current. case the feed conductors d and c are conductively connected by means of a bow 1'. This bow may be rigid or elastic, solid or divided, may consist of one or several windings and may be in one piece with the current feed conductors or rigidly or detachably combined with the same. The attachment of the incandescence body it is shown at the terminal 01 by ineans of a screw, while at 6 it is welded on.

bulb a is divided at some point is. The lower part is then connected to the other part after the incandescence body has been attached and the parts may either be fused together or, may be held together by air pressure when the lamp is evacuated, in

which case all the devices, necessary for the i current feed by means of air pressure, may also be utilized for this air tight connection of the two parts of the bulb. This lamp is glowed by induction, in that an alternating field is taken through the bow i, advantageously by means of an iron core 72. .I f the bow 2' is detachably arranged, this lamp may be easily converted into one like that illustrated in Fig. 1, for continuous and alternat- 1 ing current. Clamps Z are provided at the contacting surfaces 0 and which are intended to prevent the bulb from falling off, in the event of air penetrating to the interior of the lamp. Other devices may also serve the same purpose, such as chains, wire basa The 5 kets, protecting nets or outer globes. point of connection Z. may also be provided with like or similar safety devices. A. labyrinth packing m is provided between f and 0 having several packing rings, while liquid seals having tlutings or grooves are illustrated between 9 and c. A liquid seal between 6 and f is illustrated in Fig. 3 in detail, showing grooves n and projections 0 extending down into the liquid filling the grooves.

In the embodiment illustrated in Fig. at the conductor connecting the current feed is developed in the form of a plate 1, while the magnetic alternating field is generated in the space 7), left free between the corresiiondingly prolonged necks b and c of the bulb a.

connection with the incandescence body it In this i The attachment may be 1 etfected in any desired manner. This form of attachment may be carried out in that the 5 The feed conductors d and 0 may i be made in one piece with the part q. T heir 3 i may be etfectedin the same manner as that 1 described with reference to Fig. 1. In this 1 case also rafety clamps Z are provided, while the sealing of the contacting surfaces is .as 1 sist'ed in this case for instance, by means of l a packing medium It is not necessary that the contacting surfaces, at which the T feed conductors are air tightly connected to the lamp, by means of the air pressure, are arranged on the bulb itself. This may be effected by means of one or more intermediate members, which may be attached to the bulb in suitable manner.

Fig. 5 illustrates an example of this form of the invention. The feed conductors e (,Z are mounted with their lateral sealing surfaces on an insulating plate It, which may consist of any insulating material. The reliability of seal may be augmented by means of overlapping flanges, or grooves. After the incandescence body It has been attached to the feed conductors (l c, the plate t is placed on the bulb, on to which it is pressed by the evacuation of the latter. If the material chosen for the plate t does not offer sufficient resistance to the air pressure, or is Q the bulb, a plate u of suitable material such for instance as glass or metal may be i interposed, in which case, however, it must be insulated as regards the feed conductors. Then the seal between a and u will be secured, while the seal between it and 23 will i not present much difiiculty in view of the i large size of the surface, more especially if the labvrinth form of packing is employed. In this case the sealing surfaces of the feed conductors will be hold tight by the air pressure in the above described manner, at the 1 plate L and thus with the lamp. In order to attain like phases or conductor loads, I when two or multiple phase current, or mull tiple wire continuous current is employed, incandescence bodies may be employed haviug two or more branches and each branch i may be provided with a current feed. The bulbs accordingto Figs. 1, '2 and i may then be provided with three or more necks.

I claim as my invention 1. In an incalulescent electric lamp, a globe having a part provided with openings for the feed conductors, said part havl ing transversely disposed bearing surfaces around said openings, and feed conductors 1 having transversely extending bearing surfaces corresponding to said first named bearing surfaces, said parts being held together solely by atmospheric pressure.

2. An incandescent electric lamp comprising a globe having transversely arranged plain flat surfaces. and feed conductors having corresponding plain flat surfaces, said parts being held togeth solely by atmosl phcric pressure.

; not suitable to form a seal with the edge of 3. An incandescent eleelrir lamp eompris- 3' In testimony whereof T allix my Agnature ing a globe luwing transversely arranged in the presence nl two \\'lllle. e plain lat surfaees. feed conductors having mrrespnmling transversely extending bear- 5, ing snrfaeesl and a liquid seal interposed l)0- tween said bearing surfaces, said parts being i \Yilnesses: 1

- l held together solelyby atmospheric pressure.

()TTO SCHALLF. IL 

